At times it may be important to hold and/or transport medical or laboratory tubes in either a generally upright vertical orientation or in a generally horizontal orientation, and to be able to quickly and easily change between the two orientations. One such tube with such requirements is a urine sample tube recently developed and sold by the assignee of this application under the trademark CEN-SLIDE.RTM.. This particular tube is disclosed in detail in U.S. Pat. Nos. 5,030,421 and 4,865,812.
Briefly, this tube has an elongated generally tubular tapered body. The larger end is open and is provided with a suitable closure. The smaller end is connected to a generally flat rectangular viewing slide panel or section. The viewing section has a thin flat interior compartment that is in communication with the smaller end of the tubular body.
The tube is adapted to be mounted in a centrifuge with the tube extending outwardly and downwardly from the axis of rotation at about a forty-five degree angle. The tube is oriented so that the flat slide viewing section lies in a vertical or upright plane. As the tube is rotated by the centrifuge, the viewing section is lightly engaged by suitable means in the centrifuge to apply a tapping or flicking action to the viewing section. This action helps to evenly distribute cells and/or sediment from the urine sample evenly throughout the interior compartment of the viewing section.
It is highly desirable that, after the centrifuging, the tube then be maintained with the plane of the viewing section generally horizontal while the tube is being transported to the microscope and when the rack holding the tube is set down by the microscope. This allows the cells and other matter dispersed over the viewing section to settle into horizontal layers extending across the viewing section. The viewing section then serves as a viewing slide that can be positioned under the microscope to observe the sample within the viewing section compartment.
In addition, prior to centrifugation, it is desirable that the tube be maintained in a generally upright or vertical orientation so that it can be conveniently filled and so that added material such as reagents, stains, dip strips and the like may be inserted into the open larger end of the tube.
It is also important that the surfaces of the slide section not be impacted and thus scratched while the tube is being supported or transported.
Further, it is highly desirable that the tubes as well as their contents be fully observable from all angles while they are being supported. For example, this allows ready identification of particular tubes and also continued observation of the condition of the various tubes at various times.
Prior art racks or holders tended to hold sample tubes in either an upright or a horizontal position, and not selectively in either of those positions. Such prior art racks normally had openings larger than the cross section of the tube and relied on a support plate or other support structure to engage and support the lower inserted end of the tube. This could result in scratching or marring the sensitive viewing surfaces of the viewing panel of the CEN-SLIDE.RTM. sample tube or comparable tubes.
Such prior art racks were normally opaque and thus provided limited visibility of the tubes and the contents of the tubes.
The prior art racks normally included holding or handle means that supported the rack so that the tubes were held in a generally upright or vertical position. As noted above, supporting the centrifuged CEN-SLIDE.RTM. sample tubes in such a vertical position, with the slide viewing panels in a generally upright plane, while the tubes were carried from one location to another could undesirably change or distort the sample within the viewing panel. In this connection, the array of cells and other particulate components disbursed in the specimen sample in the slide panel would tend to shift and congregate toward the lower end of the viewing panel.